1. Field of the Invention
The present invention relates to a foldable photographic apparatus.
2. Description of the Prior Art
A foldable photographic apparatus has been introduced in a variety of models heretofore, and particularly recently it is found in a large number in a photographic apparatus using film units of a self-developing type, that is, so-called "instant photographic apparatus." Such an instant photographic apparatus uses sheet shape film units of self-developing type such as the one disclosed in the specification of the U.S. Pat. No. 3,682,076, etc. Such film units do not employ a method wherein a negative image only is formed on a film, then said negative image is enlarged, for forming a positive image on another photographic paper like an ordinary 35-mm size roll film. Instead it employs a method wherein a positive image is formed directly on an exposure surface being exposed, then said image is to be seen and appreciated in its very size without being enlarged, therefore if a film size is too small, it is hard to see and appreciate the same. Thus the size of a film unit of a self-developing type is much larger than that of a roll film of said 35-mm size. Therefore a shape of a photographic apparatus itself becomes larger resulting in poor portable characteristics.
Because of this reason, various design improvements have been made to fold an instant photographic apparatus when it is not in use or it is carried around into a neat and compact shape so that it can be placed in a pocket of a photographer for carrying.
As a typical example of such foldable photographic apparatus, there is a self-developing photographic apparatus as disclosed in the specification of U.S. Pat. No. 3,810,211. Said apparatus is made as a photographic apparatus of the TTL type in which an object light beam passing through a photographic lens system is selectively guided by a reflecting mirror provided within an exposure chamber to a finder optical system and an exposure position at which said film unit is positioned. However, said photographic apparatus has the shortcomings wherein an optical path of said finder optical system must be temporarily closed to prevent external light coming in from the finder optical system in an adverse manner from exposing the film unit, and a shutter mechanism for that purpose involves complicated structure, and, further, a photographer viewing through said finder optical system can not see an object when the film unit is being exposed.
Because of this reason, in place of a photographic apparatus of TTL a foldable photographic apparatus in which an object can be seen even during exposure of a film unit by providing a finder optical system which is independent from a photographic optical system is shown in the specification of the U.S. Pat. No. 3,678,830, etc. In this photographic apparatus, a housing section having said photographic optical system provided therein and a housing section having said finder optical system provided therein are placed at positions entirely different from each other. Therefore, if a photographer wants to make focusing adjustment of said photographic optical system while viewing through a finder optical system, various complicated linking mechanisms are required for making associated adjustment between a finder optical system and a photographic optical system which are largely separated from each other by one adjustment member. Thus, the associated arrangement is quite complicated.